Is there such a thing as a truly selfless act?

Yes, there is such thing as a selfless act. It's when you give up Godliness and become human knowing your fate as the son of God. Then when the time comes you allow yourself to be mocked, spat upon, falsely accused, humiliated, scourged (large whips with hooks) until so much of your skin is ripped off that your bones are showing and you know longer look human, then let them put a crown of thorns on your head that pierces your skull in numerous places (3-inches deep in some), then (with your body in the condition it's in) carry a huge cross they've given you to Golgotha, let them pierce your hands and feet while driving them into your large wooden cross which is giving you splinters on your skinless back, then wait until you die, then go to Hell for three days and finally come back to life. And all of this was to save the very people who did this to you. But even after you did all that, people still doubt you love them or that you are really the son of God and blame other humans' behaviours on you. You get things making fun of you, even. That seems pretty selfless to me. Thumbs up for Jesus!